max hair count with Ornatrix and VrayHairMtl

[oglu]

it seems that ram is the limming factor here...
how much hair should i be able to render with 16gb of ram...?
is a hair count of 3mio possible..?

i have only 8gig ram in my test system here so i cant test i myself...
are there any infos out there..?

[vlado]

It's not only the hair count that matters, but also the number of segments for the hairs, and how much of the hair is visible at any given time. It's difficult to say if 16 GB will be enough, especially if there are other things in the scene... A quick test with 3 million hairs and the default 10 points per hair takes about 13 GB on my machine without GI; with GI, it takes perhaps twice that amount because more of the hair had to be generated. Adjusting the raycaster parameters may help to reduce the RAM though.

As a reference, humans have from 90,000 to 140,000 hairs on the head.

Best regards,
Vlado

[oglu]

thanks for info vlado... hmm thats more ram usage than i thought...

[oglu]

seems to be impossible to get really high hair counts... id like to do some furry monster with a lot of hair all in one scene... i speak here of 20mio hairs...

[vlado]

That would be a bit too much right now indeed... we are working to reduce the memory usage for hair, but this is still some time away. Also right now a lot of the hair data is duplicated in Ornatrix and V-Ray, which makes matters worse.

Rendering the hair as a post-effect might work better in this case.

Best regards,
Vlado

[oglu]

thanks for the info vlado...
hair/fur is coming more and more important also for smaller studios... in the past only the big ones could do decent hair... but thats changing now...
there are some really great tool coming up... yeti, ornatrix 2, xgen...
i hope vray will be able to render hair much faster in the future....

[vlado]

i hope vray will be able to render hair much faster in the future....

Yes, we are hard working on this.

Best regards,
Vlado